Is there still a need for selective GC detectors?

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1 Is there still a need for selective GC detectors? M Ramesh Application Engg Agilent Technologies India Pvt Ltd.

2 Outline GC Detectors Available from Agilent Electron Capture Detector (ECD) Nitrogen Phosphorus Detector (NPD) Flame Photometric Detector (FPD) Sulfur and Nitrogen Chemiluminescence Detectors (SCD/NCD) Inductively Coupled Plasma/Mass Spec as a GC Detector (ICP-MS)

GC Detectors Available Through Agilent Thermal Conductivity Detector (TCD) Flame Ionization Detector (FID) Micro Electron Capture Detector (µecd) Nitrogen Phosphorus Detector (NPD) Flame Photometric

3 GC Detectors Available Through Agilent Thermal Conductivity Detector (TCD) Flame Ionization Detector (FID) Micro Electron Capture Detector (µecd) Nitrogen Phosphorus Detector (NPD) Flame Photometric Detector (FPD) Sulfur Chemiluminescence Detector (SCD) Nitrogen Chemiluminescence Detector (NCD) Inductively Coupled Plasma-Mass Spec (ICP-MS) Mass Selective Detector (MSD) Triple Quadrupole MS (QQQ-MS)

4 Typical Detector Operating Ranges µecd FID TCD NPD (P) AED NPD (N) MSD FPD (P) SCD (S) PFPD (S) HID (SIM) FPD (S) (SCAN) ICP-MS ppt ppb ppm 0.1% fg pg ng µg mg

5 Analysis of PCBs in Fish Oil Using GC with Dual ECD Detectors - Background Fish are an excellent source of omega-3 fatty acids (DHA & EPA) American Heart Association recommends eating fatty fish at least two times per week or taking a daily fish oil supplement g of DHA + EPA /day significantly reduces deaths from heart disease and all causes But fish and fish oil may contain pollutants: PCBs, PBDEs, PCDDs, PCDFs, & heavy metals American Heart Association (

6 PCB Analysis: Agilent 7890A with Deans Switch for Heart Cutting and Backflushing ECD 1 No Cut restrictor solenoid valve (off) S/S Inlet PCM psig psig DB-XLB ECD 2 DB-200

7 Heart Cutting with the Deans Switch to Isolate Target PCBs from Fish Oil Spiked with Aroclor 1260 Hz Hz 4000 Column 2: DB P/N E C D 1 A, E C D 1A, F ron t S ign al (C H U A N H O N G F IS H O IL D A T A J A N \ P C B \P C B 0 2-C A L IBR A T IO N IN IS O - O C T A N E Column 1: DB-XLB 30 0 P/N min Heart Cuts min

$D\FID1A.CH 2nd Blank run 0 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 0 0 0 0 0 0 1st Blank run 0 0 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 0 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 Highlighted areas are backflushed$

8 GC-FID Chromatogram of Fish Oil with No Backflushing 0 1-µL splitless injection of 10% fish oil without backflushing. GC oven was held at 290 o C for 30 min at the end of the run. Signal: FISHOIL H2.D\FID1A.CH 2nd Blank run st Blank run Highlighted areas are backflushed

9 Deans Switch in Backflush Mode Backflushing Column (3 295 o C) ECD 1 S/S Inlet PCM psig psig DB-XLB ECD 2 restrictor DB-200 solenoid valve (off)

10 Retention Time Precision Column 1 with and without Backflushing N or m Runs with Backflushing N or m Runs without Backflushing Retention times shift ~4-5 sec during 10 runs m in m in

11 Comparing Area Count Stability on Secondary Column for 2 PCBs With and Without Backflushing Comparing PCB Area Counts on Column 2 With and Without Backflushing in a 10-Injection Series Raw Area Counts PCB 118 PCB No BF 153 No BF Injection number

NPD: Blos Bead Better Results, Longer Lifetime Longer bead lifetime (2 3X) More stable operation throughout the bead s lifetime For nitrogen containing compounds similar sensitivity and selectivity

12 NPD: Blos Bead Better Results, Longer Lifetime Longer bead lifetime (2 3X) More stable operation throughout the bead s lifetime For nitrogen containing compounds similar sensitivity and selectivity specifications For phosphorous containing compounds superior sensitivity and selectivity specifications Superior resistance to ambient humidity and moisture The Blos bead is available as an aftermarket consumable (part number G ) to retrofit into existing 6890 and 7890 NPDs.

13 What s better about the Blos bead NPD (vs today s white ceramic bead NPD) Agilent s Blos NPD bead perfomance Blos vs. Ceramic Nitrogen containing compounds specs: - Similar* sensitivity (pg/s) 0.4* Similar selectivity (gn/gc) 25,000 25,000 * some users got 2-3X improvement in N signal/noise Phosphorous compounds specs: - Superior sensitivity (pg/s) Superior selectivity (gp/gc) 200,000 75,000

14 NPD Jets, Standard vs Extended Tip NPD Jet Tip extends ~ 9mm beyond old one Analytes are positioned closer to the bead, minimizing tailing. G Standard Capillary Jet G Optional Capillary Jet with extended tip

15 Drug Standard by NPD using Different Jets pa 1000 *NPD1 B, (NPD\ D) *NPD1 B, (NPD\ D) Blue is Extended Tip, less tailing Red is Standard Tip, more tailing min

16 Extended NPD Jet For Improved Nitrogen Extended Jet Part Numbers are the same for 6890 and 7890: G NPD Jet Capillary Detector G NPD Jet Universal Detector The extended jet comes installed in all 7890 NPDs (with a the standard jet in the ship kit for legacy SOP requirements) The standard jet came installed in all 6890 NPDs (with a the extended jet in the ship kit for last ~year of 6890s shipped)

17 Tox Screen of Whole Blood, GC/NPD/MSD 1 Nicotine 2 Nicotinamide 3 Carisoprodol artifact 4 Cotinine 5 Meprobamate 6 Caffeine 7 Carisoprodol 8 Methadone 9 Cyheptamide (ISTD) 10 Oxycodone 11 Cholesterol Scan TIC Column effluent split between NPD and MSD NPD

18 Improvements to Agilent s Flame Photometric Detector (FPD) for P and S Previous Agilent FPD Enhanced Agilent FPD Sulfur Sensitivity (pg/sec) Phosphorus Sensitivity (fg/sec) Sulfur Selectivity (gs/gc) Phosphorus Selectivity (gp/gc) Maximum Temperature ( o C) X X X X New optics include both a lens and wide-band optical filter set New transfer line design eliminates leaks Upgrade kits available for 6890 & 6850 FPDs

19 Pesticides: Three Way Splitter with Makeup 1X method with 1:1:1/10 split FPD:MSD:ECD Auto-sampler Phosphorus FPD AUX EPC 3.8 psig µecd 3-Way Splitter with Makeup 7890 GC Column 30 m X 0.25 mm id X 0.25 um HP-5MS 5975C MSD

20 Milk Extract (1 injection) Full scan TIC SIM µecd FPD(P)

Nitrogen and Sulfur Chemiluminescence Detectors Acquired by Agilent in December 2006 from

Sulfur chemiluminescence detection growing use corresponds to increasing regulation of sulfur

Nitrogen chemiluminescence detection is complementary to the sulfur detector in both

21 Nitrogen and Sulfur Chemiluminescence Detectors Acquired by Agilent in December 2006 from General Electric Primarily applied in the energy and petrochemical industries. Sulfur chemiluminescence detection growing use corresponds to increasing regulation of sulfur monitoring in fuels worldwide. Nitrogen chemiluminescence detection is complementary to the sulfur detector in both technology and application. Chemistry Behind Detector Operation Nitrogen (NCD) R-N + O2 NO NO + O3 NO2* NO2 + hν ( nm) Sulfur (SCD) R-S + O2 SO SO + O3 SO2* SO2 + hν ( nm)

22 Key Attributes of NCD and SCD High Selectivity No Quenching Highest selectivity for Nitrogen and Sulfur over Carbon Detector response not inhibited by hydrocarbons Equimolar Simplifies quantification of unknowns Linear Simplifies calibration Fast Options for fast GC or comprehensive 2D GC Complimentary NCD and SCD complement other Agilent detectors, such as NPD, FPD, FID and MS (e.g. for nitrosamines)

23 Sulfur Selective Detector Comparison Detector Sensitivity (pg S/sec) Selectivity (g S/g C) Other Properties FPD Nonlinear, quenching PFPD < Nonlinear; quenching not as bad, less repeatable AED ~ Linear, equimolar, true multielement ICP-MS ~1 ~ 10 9 Linear, equimolar, expensive SCD* <0.5 > 10 7 Linear, equimolar

24 Example of Sensitivity and Selectivity - SCD

25 Key Points SCD Highest sulfur selectivity over carbon Very little or no quenching Linear and equimolar response Simultaneous FID SCD Signals are possible 16 S NCD Highest nitrogen selectivity over carbon Very little or no quenching Linear and equimolar response Most stable nitrogen detector Designed with selective nitrosamines mode 7 N 14.01

26 Sulfur Determination in Fresh and Roasted Garlic by Static Headspace GC Sulfur Chemiluminescence Fresh Garlic 16 S Roasted Garlic

27 Selected Nitrosamines by GC/NCD 1 µl injection of a 2.0 µg/ml standard, 10:1 split 7 N pg each on column Peak Compound 1 N-Nitrosodimethylamine 2 N-Nitrosomethylethylamine 3 N-Nitrosodiethylamine 4 N-Nitrosopyrrolidine 5 N-Nitrosomorpholine 6 N-Nitrosodi-n-propylamine 7 N-Nitrosopiperidine 8 N-Nitrosodi-n-butylamine 9 N-Nitrosodiphenylamine

28 The Inductively-Coupled Plasma Q A A A

29 The Domain of ICP-MS Traditional Elements Impossible Elements Non-Traditional Elements

30 6890 GC coupled to 7500 ICP-MS Silcosteel lined heated transfer line and heated ICP torch injector both under 6890 control (Aux heated zones) Bidirectional communication between GC and ICP-MS via APG remote GC control via GC LUI or co-resident GC chemstation

31 Where would you use it instead of other element specific detectors? Need to measure multiple elements simultaneously (universal and specific at the same time) Need better selectivity than ECD or ELCD (comparable sensitivity for Cl, better for heavier halogens) Need better sensitivity than FPD or PFPD Need isotopic information (IDMS) Need larger dynamic range (larger than any other GC detector)

32 Sulfur in CARB Low Sulfur Reformulated Gasoline Sulfur 32 elemental chromatogram on top, Carbon 13 chromatogram inverted below Abundance Ion (31.70 to 32.70): GAS02.D Ion (12.70 to 13.70): GAS02.D (*) 16 S Time-->

33 Why ICP-MS as a GC detector for PBDEs? Sensitive (low fg sensitivity, reduced need for preconcentration or large volume injections) Specific (no interference from other halogenated compounds) Wide linear range Compound independent response (can quantify without standards) Tolerant of wide range of GC gases and flows MS confirmation of Bromine isotope ratios

34 Low fg Sensitivity for PBDEs with No interference from other halogens 35 Abundance Br Ion (34.70 to 35.70): STD100W.D (*) Ion (78.70 to 79.70): STD100W.D PBDEs PCBs Cl Time--> Extracted ion chromatogram, m/z 79 (Br) and 35 (Cl, inverted) of mixture of 50 ppb PBDE mix spiked into 500 ppm total PCB as Aroclors 1016 and 1260 (hydrogen carrier)

35 Organotins in marine sediment CRM Sn DBT TBT Signal intensity / CPS MBT TPrT DL ~ 0.03pg as Sn Sn Time / s GC-ICP-MS chromatograms of 118 Sn and 120 Sn obtained for spiked PACS-2 extract Data kindly provided by Dr. Kazumi Inagaki, National Metrology Institute of Japan 120 Sn 50 Sn

36 Iodophenols in river water by SPME/GC/ICP-MS Data kindly provided by Rodolfo Wuilloud et. al. University of Cincinnati DL ~ 0.1 ppb

37 P, S, Cl, Br and I containing pesticides GC-ICP-MS DL ~ ppb Dichlobenil, 2,4,6-TBA, DBOB, Phorate, PCNB, Terbufos, Diazinon, Malathion, Dursban, Ioxynil

38 The End

39 References Element Selective GC Detectors ECD Philip L. Wylie, Direct Injection of Fish Oil for the GC-ECD Analysis of PCBs: Results Using a Deans Switch With Backflushing, Agilent Application Note EN, January NPD Sindy Zhou and Han-wen Wang, Improving your NPD System Efficiency, Agilent Application Note EN, October 2004 Bruce Quimby, Improved Forensic Toxicology Screening Using A GC/MS/NPD System with a 725-Compound DRS Database, Agilent Application Note EN, May 2008 Blos technology enhances NPD lifetime and stability, US/Products/Instruments/gc/Pages/gp66770.aspx FPD Chin-Kai Meng, Improving Productivity and Extending Column Life with Backflush, Agilent Application Note EN, December 2006 Chin-Kai Meng and Mike Szelewski, Replacing Multiple 50-Minute FPD/ELCD/SIM Analyses with One 15-Minute Full-Scan Analysis for 10x Productivity Gain, Agilent Application Note EN, November 2007

40 References Element Selective GC Detectors (Continued) SCD/NCD ChunXiao Wang, Dual Channel Simulated Distillation of Carbon and Sulfur with the Agilent 7890A GC and 355 SulfurChemiluminescence Detector, Agilent Application Note EN, Dec Sulfur Compounds in Air Agilent Model 355 SCD, Agilent Technical Overview EN, May 2007 Agilent Model 355 Sulfur Chemiluminescence Detector (SCD): Wine Samples, Agilent Technical Overview EN, June 2007 Agilent Model 355 Sulfur Chemiluminescence Detector (SCD): Sulfur Simulated Distillation, Agilent Technical Overview EN, June 2007 Agilent Model 255 Nitrogen Chemiluminescence Detector (NCD) Simultaneous Hydrocarbon Analysis with the NCD and an FID, Agilent Technical Overview EN, May Nitrosamine Analysis by Gas Chromatography and Agilent 255 Nitrogen Chemiluminescence Detector (NCD), Agilent Technical Overview EN, August 2007 ICP-MS Steven Wilbur, GC-ICP-MS a Powerful Alternative for Detection of Brominated Flame-Retardants, eseparation Times, Vol 18:2, Raimund Wahlen, A Comparison of GC-ICP-MS and HPLC-ICP-MS for the Analysis of Organotin Compounds, Agilent Application Note EN, August 2002 Steven M. Wilbur and Emmett Soffey, Quantification and Characterization of Sulfur in Low Sulfur Reformulated Gasolines by GC-ICP-MS, Agilent Application Note EN, August 2003

GC Analysis of PCBs in Fish Oil by Direct Injection Without Any Sample Cleanup. Philip L. Wylie, Ph.D. Sr. Applications Chemist Agilent Technologies

GC Analysis of PCBs in Fish Oil by Direct Injection Without Any Sample Cleanup Philip L. Wylie, Ph.D. Sr. Applications Chemist Agilent Technologies Pittsburgh Conference, 2008 Paper 1120-1 Tuesday, 8:30